SU632080A1 - Analogue-digital function generator - Google Patents

Description

The invention relates to the field of power engineering and measurement technology, in particular to functional voltage-code converters. Functional analog-to-digital converters are known which contain a non-linear code-voltage converter included in the feedback device l. The accuracy of converting these devices is not enough. Also known is an analog-to-digital converter containing a code-voltage converter, the input of which is connected to the input of a comparison device, a logic element AND, through which the pulse generator and the comparison device are connected to a pulse counter 2. However, such a converter does not implement a logarithmic relationship between input and output. The aim of the invention is to enhance the functionality of the device. The goal is achieved by the fact that the proposed converter additionally introduces a register of intermediate values, a shift register and an increment adder, the control inputs of which are connected to the output of the AND gate, the accumulator and the code switch. The first output of the register of intermediate values is directly, and the second through the shift register is connected to the outputs of the increment adder, the output of which is connected to the input of the register of intermediate values and the input of the accumulator adder. The input of the code switch is connected to the output of the pulse counter, and the first and second outputs are connected respectively to the inputs of the code converter and the accumulator. The drawing shows a structural electrical circuit of the device. The functional analog-to-digital converter contains a comparison device 1, one input of which is supplied with input voltage U, and the other input is connected to a linear converter code-voltage 2, the output of the comparison device I is connected to one of the inputs of the logic element 3, the other input which is connected to the pulse generator 4, and the output to the pulse counter 5, register 6, shift register 7 and increment accumulator 8. One input

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register b is connected to the adder 8 directly, and the other through a register, shift 7. The output of the adder 8 is connected to the input of the register 6 and the accumulator 9. The input of the code-voltage converter 2 is connected via a switch 10 to the output of the accumulator 9 or counter 5,

The input voltage is applied to the comparative device 1. At the beginning of the conversion, after the arrival of the signal, all registers, adders and counters are reset to their initial position, the AND 3 logic element is open, and the counter 5 starts counting the number of pulses coming from the generator 4.

The operation of the device is carried out in several steps of balancing the input voltage with a compensating voltage from the output of the code-voltage converter 2 in synchronism with the clock pulses coming from the AND 3 element.

In the logarithm mode, the converter code-voltage 2 is connected through a switch of codes 10 with the input of accumulator-accumulator 9. The code of the sum of current values is fed to the input of the code-voltage converter 2, generating a compensating voltage proportional to this sum, which is compared with the input voltage .

Depending on the result of the comparison, the comparison device 1 generates a signal allowing or prohibiting the passage of the next pulse from generator 4 through element 3 to counter 5 and to shift control and summation in registers b, 7 and adder 8 in the next step of the iterative process,

At the end of the iterative process, the Neog code is formed at the output of the device. It is the numerical equivalent of the logarithm of the input value UBX. and in logarithm mode. At the same time, the input voltage is compared with the compensating voltage proportional to the code recorded in the counter 5, and the output code Mehr is generated in the accumulator 9

Claims (2)

1.US patent B 3646548, cl. 340-347, 03.21.72. 2. Gitis E.I. Information converters for electronic digital computing devices. M., Energie, 1970, p.304.